CO2 capture via catalytic hydrogenation to methanol: Thermodynamic limit vs. ‘kinetic limit’

E. FORNERO; D. CHIAVASA; A. BONIVARDI; M. BALTANÁS

CATALYSIS TODAY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2011 vol. 172 p. 158 - 165

0920-5861

The production of methanol via the catalytic hydrogenation of carbon oxides was simulated in a reactingsystem that included the recycling of noncondensable gases (H2, CO2 and CO) to evaluate the CO2capture capability of the process. As a first step, the asymptotic responses of the system ‘operating inthermodynamic equilibrium’ (i.e., overall recoveries of CO2 and H2, CH3OH selectivity and productivity)were analyzed for various industrial conditions of pressure (3–5 MPa), temperature (508–538 K), feedcomposition (H2/CO2 = 1.5/1 to 4/1) and mole recycle ratio (R) with respect to the molar feed flow rate.Then the performance of two catalysts (a novel one, Pd–Ga2O3/SiO2 and a commercial CuO/ZnO/Al2O3type) in an ideal isothermal, isobaric, pseudohomogeneous fixed-bed reactor was studied for a broadrange of W/FCO2 ratios.It was found that, whereas the ‘reactor in equilibrium’ would allow up to 100% CO2 capture, the capturevalues upon using these catalysts were significantly lower. Nevertheless, such recoveries alwaysincreased whenever R was raised, which implies that catalyst development efforts in this field shouldprioritize achievement of the highest catalytic activity (i.e., specific productivity) rather than attemptcatalyst selectivity improvements.